RESUMEN
Homocysteine, methionine, methylmalonic acid and 2-methylcitric acid are clinically relevant markers in the methionine, propionate, and cobalamin metabolism. This study aimed to develop and validate an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for simultaneously determining total homocysteine, methionine, methylmalonic acid and 2-methylcitric acid in dried blood spots. Three 3.2 mm discs were punched from each calibrator, quality control, and sample dried blood spot into a 96-well U-plate. Each sample was spiked with internal standards and extracted. Then the supernatant was transferred to another 96-well U-plate. After nitrogen drying, the dried residues were reconstituted, centrifuged, and the resulting supernatant was transferred to another 96-well plate for analysis. The method was performed using UPLC-MS/MS within 3 min, validated according to guidance documents, and applied to 72 samples from confirmed patients with methionine, propionate, and cobalamin metabolism disorders. The UPLC-MS/MS method provided satisfactory separation of the four analytes. The R2 values were ≥ 0.9937 for all analytes. The recoveries ranged from 94.17 to 114.29 %, and the coefficients of variation for intraday and interday precision were 0.19 % to 5.23 % and 1.02 % to 6.89 %, respectively. No significant carry-over was detected for the four analytes, and most of confirmed samples exhibited biomarker patterns characteristic of the relevant disorders. A simple and fast UPLC-MS/MS method was successfully developed, validated, and applied to clinical samples for the simultaneous determination of total homocysteine, methionine, methylmalonic acid, and 2-methylcitric acid in dried blood spots.
Asunto(s)
Citratos , Pruebas con Sangre Seca , Homocisteína , Límite de Detección , Metionina , Ácido Metilmalónico , Espectrometría de Masas en Tándem , Humanos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Homocisteína/sangre , Homocisteína/análogos & derivados , Ácido Metilmalónico/sangre , Ácido Metilmalónico/análogos & derivados , Pruebas con Sangre Seca/métodos , Reproducibilidad de los Resultados , Metionina/sangre , Metionina/análogos & derivados , Metionina/química , Modelos Lineales , Citratos/sangre , Citratos/química , Masculino , Femenino , PreescolarRESUMEN
BACKGROUND AND OBJECTIVES: Metabolomics facilitates the discovery of biomarkers and potential therapeutic targets for CKD progression. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We evaluated an untargeted metabolomics quantification of stored plasma samples from 645 Chronic Kidney Disease in Children (CKiD) participants. Metabolites were standardized and logarithmically transformed. Cox proportional hazards regression examined the association between 825 nondrug metabolites and progression to the composite outcome of KRT or 50% reduction of eGFR, adjusting for age, sex, race, body mass index, hypertension, glomerular versus nonglomerular diagnosis, proteinuria, and baseline eGFR. Stratified analyses were performed within subgroups of glomerular/nonglomerular diagnosis and baseline eGFR. RESULTS: Baseline characteristics were 391 (61%) male; median age 12 years; median eGFR 54 ml/min per 1.73 m2; 448 (69%) nonglomerular diagnosis. Over a median follow-up of 4.8 years, 209 (32%) participants developed the composite outcome. Unique association signals were identified in subgroups of baseline eGFR. Among participants with baseline eGFR ≥60 ml/min per 1.73 m2, two-fold higher levels of seven metabolites were significantly associated with higher hazards of KRT/halving of eGFR events: three involved in purine and pyrimidine metabolism (N6-carbamoylthreonyladenosine, hazard ratio, 16; 95% confidence interval, 4 to 60; 5,6-dihydrouridine, hazard ratio, 17; 95% confidence interval, 5 to 55; pseudouridine, hazard ratio, 39; 95% confidence interval, 8 to 200); two amino acids, C-glycosyltryptophan, hazard ratio, 24; 95% confidence interval 6 to 95 and lanthionine, hazard ratio, 3; 95% confidence interval, 2 to 5; the tricarboxylic acid cycle intermediate 2-methylcitrate/homocitrate, hazard ratio, 4; 95% confidence interval, 2 to 7; and gulonate, hazard ratio, 10; 95% confidence interval, 3 to 29. Among those with baseline eGFR <60 ml/min per 1.73 m2, a higher level of tetrahydrocortisol sulfate was associated with lower risk of progression (hazard ratio, 0.8; 95% confidence interval, 0.7 to 0.9). CONCLUSIONS: Untargeted plasma metabolomic profiling facilitated discovery of novel metabolite associations with CKD progression in children that were independent of established clinical predictors and highlight the role of select biologic pathways.
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Adenosina/análogos & derivados , Seudouridina/sangre , Insuficiencia Renal Crónica/fisiopatología , Uridina/análogos & derivados , Adenosina/sangre , Adolescente , Alanina/análogos & derivados , Alanina/sangre , Biomarcadores/sangre , Niño , Citratos/sangre , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Humanos , Hidrocortisona/análogos & derivados , Hidrocortisona/sangre , Masculino , Metabolómica , Estudios Prospectivos , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/terapia , Terapia de Reemplazo Renal , Azúcares Ácidos/sangre , Sulfuros/sangre , Triptófano/análogos & derivados , Triptófano/sangre , Uridina/sangreRESUMEN
SLC13A5/NaCT is a sodium-coupled citrate transporter expressed in the plasma membrane of the liver, testis, and brain. In these tissues, SLC13A5 has important functions in the synthesis of fatty acids, cholesterol, and neurotransmitters. In recent years, patients homozygous for recessive mutations in SLC13A5, known as SLC13A5 deficiency [early infantile epileptic encephalopathy-25 (EIEE-25)], exhibit severe global developmental delay, early-onset intractable seizures, spasticity, and amelogenesis imperfecta affecting tooth development. Although the pathogenesis of SLC13A5 deficiency remains not clearly understood, cytoplasmic citrate deficits, decreased energy status in neurons, and citrate-zinc chelation are hypothesized to explain the neurological deficits. However, no study has examined the possibility of specific pharmacological drugs and/or lifestyle changes synergizing with heterozygosity of SLC13A5 deficiency to increase the risk of EIEE-25 clinical phenotype. Here, we report on a heterozygous SLC13A5-deficient patient who demonstrated evidence of pharmaco-synergistic heterozygosity upon administration of metformin, valproic acid, and starvation. The report illustrates the importance of careful consideration of the potential adverse effects of specific pharmacological treatments in patients with heterozygosity for disease-causing recessive mutations in SLC13A5.
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Epilepsia/genética , Metformina/efectos adversos , Simportadores/deficiencia , Ácido Valproico/efectos adversos , Adulto , Sustitución de Aminoácidos , Amoníaco/sangre , Animales , Anticonvulsivantes/efectos adversos , Anticonvulsivantes/uso terapéutico , Trastorno Autístico/genética , Trastorno Bipolar/tratamiento farmacológico , Trastorno Bipolar/genética , Citratos/sangre , Transportadores de Ácidos Dicarboxílicos/fisiología , Proteínas de Drosophila/fisiología , Epilepsia/sangre , Epilepsia/inducido químicamente , Epilepsia/etiología , Femenino , Privación de Alimentos , Heterocigoto , Humanos , Lactatos/sangre , Longevidad/genética , Metformina/uso terapéutico , Ratones , Mutación Missense , Mutación Puntual , Trastornos Psicóticos/tratamiento farmacológico , Trastornos Psicóticos/genética , Psicotrópicos/uso terapéutico , Piruvatos/sangre , Recurrencia , Espasmos Infantiles/genética , Espasmos Infantiles/metabolismo , Simportadores/genética , Simportadores/fisiología , Anomalías Dentarias/genética , Ácido Valproico/uso terapéuticoRESUMEN
Methylcitric acid (MCA) analysis has been mainly utilized for the diagnosis of propionate disorders or as a second-tier test in newborn screening, but its utility for patients monitoring still needs to be established. We explored the potential contribution of MCA in the long-term management of organic acidurias. We prospectively evaluated plasma MCA and its relationship with disease biomarkers, clinical status, and disease burden in 22 patients, 13 with propionic acidemia (PA) and nine with methylmalonic acidemia (MMA) on standard treatment and/or after transplantation. Samples were collected at scheduled routine controls or during episodes of metabolic decompensation (MD), 10 patients were evaluated after transplantation (six liver, two combined liver and kidney, 2 kidney). MCA levels were higher in PA compared to MMA and its levels were not influenced by the clinical status (MD vs well state). In MMA, MCA was higher in elder patients and, along with fibroblast growth factor 21 (FGF21) and plasma methylmalonic acid, negatively correlated with GFR. In both diseases, MCA correlated with ammonia, glycine, lysine, C3, and the C3/C2, C3/C16 ratios. The disease burden showed a direct correlation with MCA and FGF21, for both diseases. All transplanted patients showed a significant reduction of MCA in comparison to baseline values, with some differences dependent on the type of transplantation. Our study provided new insights in understanding the disease pathophysiology, showing similarities between MCA and FGF21 in predicting disease burden, long-term complications and in evaluating the impact of organ transplantation.
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Errores Innatos del Metabolismo de los Aminoácidos/sangre , Citratos/sangre , Factores de Crecimiento de Fibroblastos/sangre , Acidemia Propiónica/sangre , Adolescente , Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Biomarcadores/sangre , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Ácido Metilmalónico/sangre , Trasplante de Órganos , Valor Predictivo de las Pruebas , Acidemia Propiónica/diagnóstico , Adulto JovenRESUMEN
Garcinia cambogia is one of the most commonly used anti-obesity dietary supplements, and hydroxycitric acid (HCA) is a major constituent in the commercial preparations of Garcinia. High doses of HCA are often consumed without much awareness of its pharmacokinetic and toxicokinetic parameters, and therefore, a complete understanding of its effects is lacking. The first step in understanding these parameters is the availability of a reliable bioanalytical method. Here, we present the first report on a UPLC-MS/MS method for analysis of HCA in rat plasma after a simplified and cost-effective protein precipitation. Chromatographic separation of the analytes in the supernatant was achieved using hydrophilic interaction liquid chromatography, where mass parameters were optimized and a rapid 5-min quantitative assay was developed. The method was highly sensitive, accurate, precise and linear in the concentration range of 10.5-5000 ng/mL (validated according to the United States Food and Drug Administration guidelines). Further, the method was successfully used to describe the pharmacokinetic profile of HCA in rat plasma after the administration of pure HCA and commercial Garcinia preparations.
Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Citratos/sangre , Citratos/farmacocinética , Garcinia , Espectrometría de Masas en Tándem/métodos , Administración Oral , Animales , Citratos/química , Suplementos Dietéticos , Modelos Lineales , Masculino , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Extractos Vegetales/farmacocinética , Ratas , Ratas Wistar , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Background and objectives: Although laparoscopic sleeve gastrectomy (LSG) is effective for obesity management, postoperative vitamin B12 (B12) deficiency is of major concern. In this cross-sectional study, we assessed the levels of B12 and its related functional biomarkers, namely, total homocysteine (tHcy), methylmalonic acid (MMA), folate, methylcitric acid (MCA), and hemoglobin (Hb), in one-year postoperative LSG patients and matched controls. Materials and Methods: Plasma B12, tHcy, MMA, folate, and MCA were measured in matched controls (n = 66) and patients (n = 71) using validated liquid chromatography-tandem mass spectrometry techniques and protocols in the United Arab Emirates (UAE). Results: The median B12 concentration in patients (177 pmol/L) was significantly lower (p < 0.001) than in the controls (334.7 pmol/L). The tHcy and MMA levels were significantly increased (p < 0.001 and p = 0.011, respectively) and folate levels were significantly decreased (p = 0.001) in the LSG patients compared to the controls. Interestingly, no significant difference in MCA levels were observed between the two groups. The levels of tHcy and MMA were concomitantly increased with the decreased folate levels in postoperative LSG patients when compared with the controls. The Hb levels were significantly lower in males and females in the patient group compared with those in the control group, respectively (p = 0.005 and p = 0.043). Conclusions: This is the first report of serum levels of B12 and its functional biomarkers in postoperative LSG patients among a local population from the UAE. Our findings revealed significant alterations of the B12 biomarkers, total B12, MMA, and tHcy in one-year postoperative LSG patients.
Asunto(s)
Gastrectomía/efectos adversos , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/diagnóstico , Deficiencia de Vitamina B 12/sangre , Deficiencia de Vitamina B 12/diagnóstico , Adulto , Biomarcadores/sangre , Cromatografía Liquida , Citratos/sangre , Estudios Transversales , Femenino , Ácido Fólico/sangre , Hemoglobinas , Homocisteína/sangre , Humanos , Masculino , Espectrometría de Masas , Ácido Metilmalónico/sangre , Emiratos Árabes UnidosRESUMEN
Double tracer studies in healthy human volunteers with stable isotopes of cerium citrate were performed with the aim of investigating the gastro-intestinal absorption of cerium (Ce), its plasma clearance and urinary excretion. In the present work, results of the clearance of Ce in blood plasma are shown after simultaneous intravenous and oral administration of a Ce tracer. Inductively coupled plasma mass spectrometry was used to determine the tracer concentrations in plasma. The results show that about 80% of the injected Ce citrate cleared from the plasma within the 5 mins post-administration. The data obtained are compared to a revised biokinetic model of Ce, which was initially developed by the International Commission on Radiological Protection (ICRP). The measured plasma clearance of Ce citrate was mostly consistent with that predicted by the ICRP biokinetic model. Furthermore, in an effort to quantify the uncertainty of the model prediction, the laboratory animal data on which the ICRP biokinetic Ce model is based, was analyzed. The measured plasma clearance and its uncertainty was also compared to the plasma clearance uncertainty predicted by the model. It was found that the measured plasma clearance during the first 15 min after administration is in a good agreement with the modelled plasma clearance. In general, the measured clearance falls inside the 95% confidence interval predicted by the biokinetic model.
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Isótopos de Cerio/farmacocinética , Citratos/farmacocinética , Modelos Biológicos , Adulto , Isótopos de Cerio/sangre , Isótopos de Cerio/orina , Citratos/sangre , Citratos/orina , Femenino , Humanos , Masculino , Persona de Mediana Edad , Incertidumbre , Adulto JovenRESUMEN
PURPOSE: Alcohol consumption is an established breast cancer risk factor, though further research is needed to advance our understanding of the mechanism underlying the association. We used global metabolomics profiling to identify serum metabolites and metabolic pathways that could potentially mediate the alcohol-breast cancer association. METHODS: A cross-sectional analysis of reported alcohol consumption and serum metabolite concentrations was conducted among 211 healthy women 25-29 years old who participated in the Dietary Intervention Study in Children 2006 Follow-Up Study (DISC06). Alcohol-metabolite associations were evaluated using multivariable linear mixed-effects regression. RESULTS: Alcohol was significantly (FDR p < 0.05) associated with several serum metabolites after adjustment for diet composition and other potential confounders. The amino acid sarcosine, the omega-3 fatty acid eicosapentaenoate, and the steroid 4-androsten-3beta,17beta-diol monosulfate were positively associated with alcohol intake, while the gamma-tocopherol metabolite gamma-carboxyethyl hydroxychroman (CEHC) was inversely associated. Positive associations of alcohol with 2-methylcitrate and 4-androsten-3beta,17beta-diol disulfate were borderline significant (FDR p < 0.10). Metabolite set enrichment analysis identified steroids and the glycine pathway as having more members associated with alcohol consumption than expected by chance. CONCLUSIONS: Most of the metabolites associated with alcohol in the current analysis participate in pathways hypothesized to mediate the alcohol-breast cancer association including hormonal, one-carbon metabolism, and oxidative stress pathways, but they could also affect risk via alternative pathways. Independent replication of alcohol-metabolite associations and prospective evaluation of confirmed associations with breast cancer risk are needed.
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Consumo de Bebidas Alcohólicas/sangre , Adulto , Consumo de Bebidas Alcohólicas/metabolismo , Androstenodiol/análogos & derivados , Androstenodiol/sangre , Neoplasias de la Mama , Niño , Cromanos/sangre , Citratos/sangre , Estudios Transversales , Dieta , Ácido Eicosapentaenoico/sangre , Femenino , Estudios de Seguimiento , Humanos , MetabolómicaRESUMEN
Deficiency of propionyl-CoA carboxylase causes propionic acidemia and deficiencies of methylmalonyl-CoA mutase or its cofactor adenosylcobalamin cause methylmalonic acidemia. These inherited disorders lead to pathological accumulation of propionyl-CoA which is converted in Krebs cycle to methylcitrate (MCA) in a reaction catalyzed by citrate synthase. In healthy individuals where no propionyl-CoA accumulation occurs, this enzyme drives the condensation of acetyl-CoA with oxaloacetate to produce citric acid (CA), a normal Krebs cycle intermediate. The competitive synthesis of CA and MCA through the same enzymatic mechanism implies that increase in MCA production is accompanied by decrease in CA levels. In this study, we assessed MCA concentration and the ratio of MCA/CA as plausible markers for propionic and methylmalonic acidemias. We measured MCA and CA in dried blood spots using liquid chromatography tandem mass spectrometry. The reference ranges of MCA, CA and MCA/CA in 123 healthy individuals were ≤0.63 µmol/L, 36.6-126.4 µmol/L and 0.0019-0.0074, respectively. In patients with propionic and methylmalnic acidemias (n = 7), MCA concentration ranged between 1.0-12.0 µmol/L whereas MCA/CA was between 0.012-0.279. This is the first report to describe the potential role of MCA and MCA/CA in dried blood spots as diagnostic and monitoring biomarkers for inherited disorders of propionyl-CoA metabolism.
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Biomarcadores/sangre , Citratos/sangre , Pruebas con Sangre Seca , Errores Innatos del Metabolismo/sangre , Propionatos/sangre , Propionatos/metabolismo , Bioensayo , Estudios de Casos y Controles , Humanos , Ácido Metilmalónico/metabolismoRESUMEN
Colorectal cancer (CRC) is one of the leading causes of cancer-related death worldwide. Colorectal adenomatous polyps are at high risk for the development of CRC. In this report, we described the metabolic changes in the sera from patients with colorectal polyps and CRC by using the NMR-based metabolomics. 110 serum samples were collected from patients and healthy controls, including 40 CRC patients, 32 colorectal polyp patients, and 38 healthy controls. The metabolic profiles and differential metabolites of sera were analyzed by multivariate statistical analysis (MSA), including principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and orthogonal partial least squares discriminant analysis (OPLS-DA) methods. A total of 23 differential metabolites were identified from MSA. According to the pathway analysis and multivariate ROC curve-based exploratory analysis by using the relative concentrations of differential metabolites, we found abnormal metabolic pathways and potential biomarkers involved with the colorectal polyp and CRC. The results showed that the pyruvate metabolism and glycerolipid metabolism were activated in colorectal polyps. And the glycolysis and glycine, serine, and threonine metabolism were activated in CRC. The changed metabolism may promote cellular proliferation. In addition, we found that the rates of acetate/glycerol and lactate/citrate could be the potential biomarkers in colorectal polyp and CRC, respectively. The application of 1H-NMR metabolomics analysis in serum has interesting potential as a new detection and diagnostic tool for early diagnosis of CRC.
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Pólipos del Colon/sangre , Neoplasias Colorrectales/sangre , Metaboloma , Acetatos/sangre , Aminoácidos/sangre , Biomarcadores/sangre , Citratos/sangre , Glicerol/clasificación , Humanos , Ácido Láctico/sangre , Espectroscopía de Resonancia Magnética/métodos , Ácido Pirúvico/sangreRESUMEN
BACKGROUND: To evaluate the effect of dextrose contained in banked blood products on the changes of blood glucose levels in adult living donor liver transplantation patients retrospectively. METHODS: Four hundred seventy-seven patients were divided into a non-blood transfusion (BT) group (G1) and a BT group (G2). The changes in blood glucose levels during the operation were compared using a Mann-Whitney U test, and a P value less than .05 was regarded as significant. RESULTS: No significant changes were detected in blood glucose levels after anesthesia, during dissection phase, in the anhepatic phase, or after reperfusion between the groups. Estimated blood loss for G1 (n = 89) and G2 (n = 388) were 718 ± 514 and 5804 ± 877 mL respectively, G1 had no blood transfusion but G2 had received 4350 ± 6230 mL leukocyte-poor red blood cell transfusion, the pre- and end operation hemoglobin for G1 and G2 were 13.2 ± 2.0, 10.2 ± 1.9 and 10.1 ± 1.6, 10.2 ± 1.9 mg/dL respectively, indicating that they were not under or over transfused. CONCLUSION: When banked blood products are used to replace ongoing blood loss, the dextrose contained in citrate-phosphate-dextrose-adenine seems to have no effect on the changes in the blood glucose levels of the recipients.
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Glucemia/análisis , Transfusión Sanguínea/estadística & datos numéricos , Hemostasis Quirúrgica/métodos , Trasplante de Hígado/métodos , Adulto , Bancos de Sangre , Citratos/sangre , Femenino , Glucosa , Humanos , Donadores Vivos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estadísticas no ParamétricasRESUMEN
The metabolic effects associated with intake of different dietary protein sources are not well characterized. We aimed to elucidate how two diets that varied in main protein sources affected the fasting and postprandial serum metabolites and lipid species. In a randomized controlled trial with crossover design, healthy adults (n = 20) underwent a 4-week intervention with two balanced diets that varied mainly in protein source (lean-seafood versus non-seafood proteins). Nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry analyses were applied to examine the effects of the two diets on serum metabolites. In the fasting state, the lean-seafood diet period, as opposed to the non-seafood diet period, significantly decreased the serum levels of isoleucine and valine, and during the postprandial state, a decreased level of lactate and increased levels of citrate and trimethylamine N-oxide were observed. The non-seafood diet significantly increased the fasting level of 26 lipid species including ceramides 18:1/14:0 and 18:1/23:0 and lysophosphatidylcholines 20:4 and 22:5, as compared to the lean-seafood diet. Thus, the lean-seafood diet decreased circulating isoleucine and valine levels, whereas the non-seafood diet elevated the levels of certain ceramides, metabolites that are associated with insulin-resistance.
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Dieta , Ayuno , Periodo Posprandial , Alimentos Marinos , Adolescente , Adulto , Anciano , Aminoácidos/administración & dosificación , Aminoácidos/sangre , Biomarcadores/sangre , Colesterol/sangre , Cromatografía Liquida , Citratos/sangre , Estudios Cruzados , Grasas de la Dieta , Metabolismo Energético , Femenino , Humanos , Isoleucina/sangre , Lisofosfatidilcolinas/sangre , Espectroscopía de Resonancia Magnética , Masculino , Espectrometría de Masas , Metilaminas/sangre , Persona de Mediana Edad , Triglicéridos/sangre , Valina/sangre , Adulto JovenRESUMEN
Gastrodia elata Blume, called Tianma in China, has been widely used to treat headaches, convulsions and epilepsy for thousands of years. In the present study, a series of optimizations were employed to develop a rapid, sensitive, and reliable high-performance liquid chromatography-triple quadrupole mass spectrometry method, which was then used for the simultaneous determination of gastrodin, parishin, parishin B, parishin C and parishin E in beagle dog plasma after intragastric administration of tall Gastrodia capsules (Tianma brand). The chromatographic separation was achieved on a C18 column with gradient elution by using a mixture of 0.4% formic acid aqueous solution and acetonitrile as the mobile phase at a flow rate of 0.15 mL/min. A tandem mass spectrometric detection was conducted using multiple-reaction monitoring (MRM) via electrospray ionization (ESI) source in negative ionization mode. Samples were pre-treated by a single-step protein precipitation with methanol, and bergenin was used as internal standard (IS). Under the optimized conditions, the lower limit of quantification (LLOQ) was 0.10 ng/mL for gastrodin, 0.40 ng/mL for parishin B, 0.02 ng/mL for parishin E and 0.20 ng/mL for parishin and parishin C, all of which previously were the highest levels of sensitivity. The methods were optimized for selectivity, calibration curves, accuracy and precision. Extraction recoveries, matrix effects and stability were within acceptable ranges. Pharmacokinetic parameters of the tested substances were also quantitatively determined. Finally, a possible metabolic pathway was induced based on correlations obtained from quantitative and qualitative data analysis in vivo.
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Alcoholes Bencílicos/sangre , Alcoholes Bencílicos/farmacocinética , Cromatografía Líquida de Alta Presión/métodos , Gastrodia/química , Glucósidos/sangre , Glucósidos/farmacocinética , Espectrometría de Masas en Tándem/métodos , Animales , Cápsulas , Citratos/sangre , Perros , Vías de Administración de Medicamentos , Masculino , Ratas Sprague-Dawley , Factores de TiempoRESUMEN
BACKGROUND AND AIMS: Increased propionylcarnitine levels in newborn screening are indicative for a group of potentially severe disorders including propionic acidemia (PA), methylmalonic acidemias and combined remethylation disorders (MMACBL). This alteration is relatively non-specific, resulting in the necessity of confirmation and differential diagnosis in subsequent tests. Thus, we aimed to develop a multiplex approach for concurrent determination of 3-hydroxypropionic acid, methylmalonic acid and methylcitric acid from the same dried blood spot (DBS) as in primary screening (second-tier test). We also set out to validate the method using newborn and follow-up samples of patients with confirmed PA or MMACBL. METHODS: The assay was developed using liquid chromatography-tandem mass spectrometry and clinically validated with retrospective analysis of DBS samples from PA or MMACBL patients. RESULTS: Reliable determination of all three analytes in DBSs was achieved following simple and fast (<20 min) sample preparation without laborious derivatization or any additional pipetting steps. The method clearly distinguished the pathological and normal samples and differentiated between PA and MMACBL in all stored newborn specimens. Methylcitric acid was elevated in all PA samples; 3-hydroxypropionic acid was also high in most cases. Methylmalonic acid was increased in all MMACBL specimens; mostly together with methylcitric acid. CONCLUSIONS: A liquid chromatography-tandem mass spectrometry assay allowing simultaneous determination of the biomarkers 3-hydroxypropionic acid, methylmalonic acid and methylcitric acid in DBSs has been developed. The assay can use the same specimen as in primary screening (second-tier test) which may reduce the need for repeated blood sampling. The presented preliminary findings suggest that this method can reliably differentiate patients with PA and MMACBL in newborn screening. The validated assay is being evaluated prospectively in a pilot project for extension of the German newborn screening panel (?Newborn screening 2020"; Newborn Screening Center, University Hospital Heidelberg).
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Errores Innatos del Metabolismo de los Aminoácidos/sangre , Citratos/sangre , Pruebas con Sangre Seca/métodos , Ácido Láctico/análogos & derivados , Tamizaje Masivo/métodos , Ácido Metilmalónico/sangre , Acidemia Propiónica/sangre , Cromatografía Liquida/métodos , Femenino , Humanos , Recién Nacido , Ácido Láctico/sangre , Masculino , Espectrometría de Masas/métodosRESUMEN
The goal of this study was to investigate metabolic risk factors in pediatric stone formers in an emerging economy. A prospective, data collection enrolled 250 children age <1-15 years at our center. Risk factors were evaluated by gender and in age groups <1-5, 6-10 and 11-15 years. Patients were evaluated for demographics, blood and 24 h urine for calcium, magnesium, phosphate, uric acid, electrolytes and additional protein, citrate, ammonia and oxalate in urine. All reported values were two sided and statistical significance was considered at p value ≤0.05. The mean age at diagnosis was 7.50 ± 3.56 years with a male to female ratio of 1.84:1. A family history of urolithiasis was found in 41 (16.4 %), urinary tract infection in 18 (7 %) and chronic diarrhea in 75 (30 %). Hypercalcemia was seen in 37 (14.8 %), hyperuricemia in 23 (9.2 %) and hyperphosphatemia in 6 (2.4 %). Urinary metabolic abnormalities were identified in 248 (98 %) of the cases. Hypocitraturia was found in 207 (82.8 %), hyperoxaluria in 62 (26.4 %), hyperuricosuria in 82 (32.8 %), hypercalciuria in 51 (20.4 %), hyperphosphaturia in 46 (18.4 %), hyperammonuria in 10 (4 %), hypocalciuria in 82 (32.8 %), and hypovolemia in 73 (29.2 %). Risk factors were similar between genders except higher rates of hyponatriuria, hypophosphaturia, and hypocalciuria in females. Hyperuricosuria, hyponatriuria, and hypovolemia were highest in 1-5 years (52, 49, 49 %) as compared to (18, 21, 12 %) those in 11-15 years (p < 0.001), respectively. This study shows that careful metabolic analysis can identify risk factors in 98 % of the children where appropriate metaphylaxis can be undertaken both for treatment and prevention of recurrence.
Asunto(s)
Diarrea/epidemiología , Infecciones Urinarias/epidemiología , Urolitiasis/epidemiología , Adolescente , Factores de Edad , Amoníaco/orina , Calcio/sangre , Calcio/orina , Niño , Preescolar , Citratos/sangre , Citratos/orina , Diarrea/sangre , Diarrea/metabolismo , Diarrea/orina , Femenino , Humanos , Incidencia , Masculino , Oxalatos/orina , Pakistán , Fosfatos/sangre , Fosfatos/orina , Prevalencia , Estudios Prospectivos , Recurrencia , Factores de Riesgo , Factores Sexuales , Ácido Úrico/sangre , Ácido Úrico/orina , Infecciones Urinarias/sangre , Infecciones Urinarias/metabolismo , Infecciones Urinarias/orina , Urolitiasis/sangre , Urolitiasis/metabolismo , Urolitiasis/orinaRESUMEN
Background Newborn screening for propionic acidemia and methylmalonic acidurias using the marker propionylcarnitine (C3) is neither sensitive nor specific. Using C3 to acetylcarnitine (C3/C2) ratio, together with conservative C3 cut-offs, can improve screening sensitivity, but the false positive rate remains high. Incorporating the marker 2-methylcitric acid has been suggested, to improve the positive predictive value for these disorders without compromising the sensitivity. Methods Between July 2011 and December 2012 at the Newborn Screening Ontario laboratory, all neonatal dried blood spot samples that were reported as screen positive for propionic acidemia or methylmalonic acidurias based on elevated C3 and C3/C2 ratio were analyzed for 2-methylcitric acid, using liquid chromatography tandem mass spectrometry. Results Of 222,420 samples screened, 103 were positive for methylmalonic acidurias or propionic acidemia using C3 and C3/C2 ratio as markers. There were nine true positives: propionic acidemia (n = 3), Cobalamin (Cbl) A (n=1), and Cbl C (n = 5). Among false positives there were 72 neonates not affected, 20 with maternal B12 deficiency, and two incidental finding (transcobalamin II and unclassified Cbl defect). 2-Methylcitric acid was analyzed in all 103 samples and ranged between 0.1 and 89.4 µmol/l (reference range 0.04-0.36). Only 14 samples exceeded the set 2-methylcitric acid cut-off of 1.0 µmol/l, including the samples from all nine true positives. Conclusion By including 2-methylcitric acid in the screening algorithm, the positive predictive value of our primary and secondary screening targets improved from 8.7 to 64.3%. This would have eliminated 89 unnecessary referrals while maintaining 100% sensitivity.
Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/sangre , Citratos/sangre , Pruebas con Sangre Seca , Tamizaje Neonatal/métodos , Acetilcarnitina/sangre , Algoritmos , Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Biomarcadores/sangre , Carnitina/análogos & derivados , Carnitina/sangre , Cromatografía Liquida , Reacciones Falso Positivas , Humanos , Recién Nacido , Ácido Metilmalónico/sangre , Valor Predictivo de las Pruebas , Valores de Referencia , Derivación y Consulta , Reproducibilidad de los Resultados , Espectrometría de Masas en TándemRESUMEN
Sodium citrate induces alkalosis and can provide a performance benefit in high-intensity exercise. Previous investigations have been inconsistent in the ingestion protocols used, in particular the dose and timing of ingestion before the onset of exercise. The primary aim of the current study was to quantify blood pH, blood bicarbonate concentration and gastrointestinal symptoms after ingestion of three doses of sodium citrate (500 mgâ kg-1, 700 mgâ kg-1 and 900 mgâ kg-1). Thirteen participants completed four experimental sessions, each consisting of a different dose of sodium citrate or a taste-matched placebo solution. Blood pH and blood bicarbonate concentration were measured at 30-min intervals via analysis of capillary blood samples. Gastrointestinal symptoms were also monitored at 30-min intervals. Statistical significance was accepted at a level of p < .05. Both measures of alkalosis were significantly greater after ingestion of sodium citrate compared with placebo (p < .001). No significant differences in alkalosis were found between the three sodium citrate doses (p > .05). Peak alkalosis following sodium citrate ingestion ranged from 180 to 212 min after ingestion. Gastrointestinal symptoms were significantly higher after sodium citrate ingestion compared with placebo (p < .001), while the 900 mg.kg-1 dose elicited significantly greater gastrointestinal distress than 500 mgâ kg-1 (p = .004). It is recommended that a dose of 500 mgâ kg-1 of sodium citrate should be ingested at least 3 hr before exercise, to achieve peak alkalosis and to minimize gastrointestinal symptoms before and during exercise.
Asunto(s)
Alcalosis/diagnóstico , Citratos/administración & dosificación , Citratos/efectos adversos , Tracto Gastrointestinal/fisiopatología , Dolor Abdominal , Adulto , Alcalosis/sangre , Bicarbonatos/sangre , Citratos/sangre , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Ejercicio Físico , Femenino , Flatulencia , Humanos , Concentración de Iones de Hidrógeno , Masculino , Calambre Muscular , Náusea , Citrato de Sodio , Encuestas y Cuestionarios , Factores de Tiempo , Vómitos , Adulto JovenRESUMEN
Investigation of toxicological effect of various metals is the field of interest for toxicological scientists since four to five decades and especially the toxicological effect of those drugs containing metals and there use is common because there is no other choice except to use these metal containing drugs. Inorganic as well as organic salts of lithium are commonly used in prophylaxis and treatments of many psychiatric disorders. The aim of the present study was to see the difference between the effect of organic and inorganic salt of lithium commonly used in psychiatric disorders on the GSH of human blood plasma. It is the scientific fact that ionic dissociation of organic and inorganic salts of any metal is always quite different hence to prove this fact, the effect of lithium citrate (organic salt of lithium) and lithium carbonate (inorganic salt of lithium) was investigated on human blood plasma GSH to find the difference between the effect of two. Ellman's method was used for the quantification of glutathione contents in plasma. It was found that lithium citrate decrease plasma GSH contents less than lithium carbonate indicating that organic salts of lithium are safe than inorganic salts of lithium when are used in psychiatric disorders. Further to analyze the effect of organic and inorganic salt of lithium on blood plasma GSH with the increase in incubation time was also evaluated and was found that both concentration and time dependent effect of organic salt of lithium shows that this salt has decreased plasma GSH contents of human blood less than inorganic salt of lithium either by promoting oxidation of GSH into GSSG or by lithium glutathione complex formation. These results suggest the physicians that the use of organic lithium salts is much safer than inorganic salts of lithium in terms of depletion of blood plasma GSH contents.
Asunto(s)
Citratos/sangre , Glutatión/sangre , Carbonato de Litio/sangre , Psicotrópicos/sangre , Biomarcadores/sangre , Citratos/toxicidad , Relación Dosis-Respuesta a Droga , Disulfuro de Glutatión/sangre , Humanos , Carbonato de Litio/toxicidad , Psicotrópicos/toxicidad , Medición de Riesgo , Factores de TiempoRESUMEN
BACKGROUND: The purpose of this study was to describe the distribution of trisodium-citrate 4% (TSC) anticoagulant (AC) between the product and the donors undergoing plasma donation. SUBJECTS AND METHODS: Data of 32 regular donors of plasma initially collected for a study published in 2010 were re-analyzed to determine the amount of citrate received by the donor and the citrate infusion rate (CIR) in mg/kg/min to the donor. Donor plasmaphereses (DP) were performed with the automated Haemonetics plasma collecting system 2 (PCS2). Plasma volume was programmed at 760 ml including AC. CIR was calculated from citrate received by the donors divided by the body weight over time. RESULTS: 130 ± 12 ml TSC was used for 760 ml plasma. An average of 110 ml TSC or 84.6% of citrate load was in collected plasma and not given to the donor. From the difference of 20 ml or 514 mg citrate an average CIR of 0.16 mg/kg/min was calculated. CONCLUSION: The total amount of citrate received by the donor is minimal and the average CIR is below the critical level of 1 mg/kg/min.